Thanks for all the feedback and suggestions. I replaced all the tubes to ensure a bad tube was not causing the issue. The fuse that is blowing is the T2A, not the T1A. I am in Canada with 120 volts, not 240. The Mains Select is set to 120 on the back of the head. I can leave the head on and...
I have a 1979 Marshall Super Lead 100-watt head that started blowing the 2amp fuse after 5 minutes on. I replaced all tubes (it was time) and it still burns a fuse, but after about 15 minutes. The impedance is properly matched with the speaker. Ihave some experience having built a couple of amp...